Impeller Question

[Tangman]

Sorry to say but if its a RS turbo pump for the skimmer and its broken, then it's not worth replacing the impeller, you mite get another 6 to 8 months out of the pump before it gets too loud to stand it. ( I had one on my 1st and 2nd tanks)
You mite even consider replacing the whole skimmer, you won't believe how junkie the RS is until you replace it with a plug the play type skimmer like a ASM or a Euroreef
just my 2 cents....